Combined testing device and machine tool



Get. 5, 1954 J. F. ROMANS EI'AL 02 COMBINED TESTING DEVICE AND MACHINE TOOL Filed Feb. 5, 1951 16 Sheets-Sheet 1 INVENTORS JOHN F: ROMA/V5 nun BY sup/701v .LiP/RMA/V 0 0L524 vi /MAJ AT7'07ENEY6.

Oct 1954 J. F. ROMANS ETAL COMBINED TESTING DEVICE AND MACHINE TOOL l6 Sheets-Sheet 2 Filed Feb. 5, 1951 INVENTORS Ja/M l-Z Palm/v: 6 BY ANTON E. P/RMQN OCt. 5, 1954 J RQMANS ETAL 2,690,702

COMBINED TESTING DEVICE AND MACH INE TOOL Filed Feb. 5, 1951 16 Sheets-Sheet 3 5'19. 6 Q u BY QNTOJV E. PmMe/v A wan/2Y6.

Get. 5, 1954 J. F. ROMANS ETAL COMBINED TESTING DEVICE AND MACHINE TOOL l6 S eets-Sheet 5 Filed Feb. 5, 1951 D r M mwwwm MA 0 PM a ET N #6 w J. F.- ROMANS ET AL COMBINED TESTING DEVICE AND MACHINE TOOL Oct 5, 1954 16 Sheets-Sheet 6 Filed Feb. 5, 1951 INVENTOR5 W/A/ E #0/64/1/ BY A/ym/v 157 /8618 YOLWJM aTTokA/fy v 0d. 5, 1954 J RQMANS ETAL 2,690,702

COMBINED TESTING DEVICE AND MACHINE TOOL Filed Feb. 5, 1951 16 Sheets-Sheet 7 INVENTORJ JOHN EPOMQ/V Mo 39 56 By A/v'ro/v EZPIRM 41v 2T 36 0% mi Q7 7 ORNEXS.

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Oct. 5, 19.54 J. F. ROMANS ETAL COMBINED TESTING DEVICE AND MACHINE TOOL l6 Sheets-Sheet 9 FiledFeb. 5, 1951 INVENTORS JOHN E HUMANS GNP ATTOIZA/CY6 Oct 1954 J. F. ROMANS EI'AL COMBINED TESTING DEVICE AND MACHINE TOOL l6 Sheets-Sheet 10 Filed Feb. 5, 1951 dig/6 INVENTORS JOHN EXPO/10AM ma BY ANTON a P/mmA/ ATTOIZIV'EVJ.

Get. 5, 1954 J. F. ROMANS ETAL 2,690,702

COMBINED TESTING DEVICE AND MACHINE TOOL Filed Feb. 5, 1951 16 Sheets-Sheet 11 INVENTORS Jay/y F. fioMmv- BY 4mm. 521mm Oct. 5, 1954 J. F. ROMANS EI'AL COMBINED TESTING DEVICE AND MACHINE TOOL 16 Sheets-Sheet 12 Filed Feb. 5, 1951 S N WWW Wm mwm m mfi m wwl Em v wafi m5 Oct. 5, 1954 ROMANS r 2,690,702

COMBINED TESTING DEVICE AND MACHINE TOOL Filed 1951 16 Sheets-Sheet 1s HOLLOW MILL FACE MILL HYDRAUUC OVERLOADS FIXTURE CLAMP CONTROL UNCLAMP OUILL m our OUILLCLAMP DELAY UNCLAMP 309' S LQE IN STOP DELAY 2B! UNCLAMP HOLLOW MILL 7 IN DWELL OUT I 326 326 MANUAL l 336 b INVENTORS Jol/N F. FO1AN5 60:0 6:29. 25

BY /VTON E. P/RMQN W LLYA AJ Patented Qct. 5, 1954 COMBINED TESTING DEVICE AND MACHINE TOOL John F. Romans, Cleveland Heights, and Anton E. Pirman, Cleveland, Ohio, assignors to The Motch & Merryweather Machinery Company, Cleveland, Ohio, a corporation of Ohio Application February 5, 1951, Serial No. 209,344

21 Claims. 1

This invention relates as indicated to a combined testing device and machine tool, and more particularly to a weighing and milling machine comprising mechanism adapted to determine the center of gravity or balance or relationship of g the weights of opposite ends of elongated objects such as connecting rods and automatically to preset appropriate machine tools such as milling machines to perform the necessary metal removing operations on the work-piece to bring the latter into desired balance and Weight.

It has long been appreciated that certain rotating and reciprocating parts of internal combustion engines, I; brought to an exactly determined weight and 1; balance in order that the engine may operate for example, require to be properly and without undue vibration For this purpose, very accurate weighing scales have been designed such as that disclosed in Hem Patent 1 No. 2, 82,052 entitled Testing Device for Determining Mass Distribution whereby the operator may read from a dial the amount of weight to be I removed from the respective end portions of the i work-piece.

The operator has then been required manually to adjust a machine tool to make the necessary metal removing cuts on such work-piece when the latter has been transferred thereto. ment into such weighing and machining opera- ;1 tions necessarily invites error in both the reading of the dial or like recording means of the weighing instrumentality and also error in seting of such machine tool.

The introduction of the human ele- Very large numbers of work-pieces such as connecting rods are commonly processed in a single day, and a great 3, deal of expensive forging and machining work will already have gone into such work-pieces 1'- prior to reaching this stage in the manufacture.

i 1 Consequently, any error now made in the removal of metal from the work-piece may result in re- 5 i jection and scrapping of the same with a resultant substantial monetary loss.

, Moreover, the work-piece has in the past required a careful preliminary machining operation in order to ensure that, when such workpiece is placed in the fixture of the milling machine or like machine tool and the latter manu- I 1 ally set by the operator, a definite uniform starting point for the milling operation will be estabremoved by the milling operation. This preliminary machining operation has also been relaweight or balance ultimately obtained in the final milling operation.

It is accordingly a primary object of our invention to provide a combined weighing and machining device which will remove substantially all possibility of human error in the operation of the same and will permit such operation to be controlled by relatively unskilled labor.

Another object is to provide a combined testing device and machine tool in which the setting of the milling or like metal-removing mechanism will be automatically controlled by the weighing mechanism when the work-piece is positioned on the latter.

Still another object is to provide a Weighing and milling machine which will be thus automatically preset by operation of the weighing mechanism to make a milling cut or cuts on the work-piece to leave the proper amount of metal thereon afiording the desired weight and balance without, as previously, being required first to establish a definite dimension on the Work-piece by a preliminary machining operation to provide a definite fixed starting position for the final milling operation in order to remove a specific amount of metal.

A further object is to provide control means for a machine tool whereby the latter may automatically probe the work-piece properly to position the cutting tool to make the correct depth of out without the necessity of previously machining the portion of the work-piece engaged thereby.

Other objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. l is a top plan view of a combined weighing and milling machine constituting one embodiment of our invention;

Fig. 2 is a front elevational view of the ma chine shown in Fig. 1;

Fig. 3 is an end elevational view of such machine;

Fig. 4 is a fragmentary elevational View of the gauging means employed to determine the depth of cut of a hollow milling cutter adapted to operate upon one end portion of a work-piece such as a connecting rod or the like;

Fig. 5 is a top plan view of the gauge mechanism of Fig. 4;

Fig. 6 is an end elevational view of such gauging mechanism;

Fig. '7 is a horizontal sectional View through the face milling mechanism and associated probe adapted to operate upon the other end portion of such work-piece, taken along the line 'I---! on Fig. 8, the extreme axially shifted positions of the milling cutter quill being indicated;

Fig. 8 is a vertical sectional view through such probing mechanism taken along the line 8-8 on Fig. 1;

Fig. 9 is an enlarged sectional detail view of such probing mechanism similar to Fig. '7;

Fig. 10 is an enlarged elevational detail view of a portion of such probing mechanism similar to Fig. 8;

Fig. 11 is a vertical sectional view through the probe control means taken on the line HH on Fig. 8;

Fig. 12 is an elevational view of the face mill quill-clamping means as viewed from the milling cutter end;

Fig. 13 is a top plan view of the gauge control means for the hollow milling cutter;

Fig. 14 is an end elevational View of such lastnamed control means;

Fig. 15 is a vertical sectional view taken along the lines 15-45 on Fig. 13 and Fig. 14;

Fig. 16 is a fragmentary vertical sectional view taken along the line l6|6 on Fig. 14;

Fig. 17 is an end elevational view of the housing of such control means taken on the line l1-i! on Fig. 13;

Fig. 18 is a top plan view of the work holding fixture adapted to secure the work-piece during performance of the milling operations;

Fig. 19 is a front elevational view of such work holding fixture partly broken away to disclose the internal construction of the same;

Fig. 20 is a semi-diagrammatic sectional View of the face milling mechanism and control means therefor generally corresponding to Fig. '7 but with the parts somewhat rearranged better to facilitate understanding of their general interrelation;

Fig. 21 is a semi-diagrammatic sectional view to show the general interrelation and cooperation of the gauging mechanism and control means for the hollow milling cutter;

Fig. 22 is an elevational view of the selsyn and drive motor for presetting the hollow milling mechanism;

Fig. 23 is a wiring diagram of the electric circuit interconnecting the weighing machine and the selsyn controlled drive motors for the milling machine control means;

Fig. 24 is a schematic diagram of the fluid pressure system for cooperation of the two milling machines and. Work clamping mechanism;

Fig. 25 is a wiring diagram of the electric circuits controlling operation of such fluid pressure system.

Fig. 26 is a simplified view of one form of weighing mechanism commercially available and suitable for our purpose; and

Fig. 27 is a side elevational view of one indicator means of such weighing mechanism together with an associated selsyn.

GENERAL CONSTRUCTION Referring now more particularly to Figs. 1, 2,

and 3 of the drawing, the embodiment of our invention there illustrated comprises a welded box-like base I having a lateral extension 2 enclosing weighing scale mechanism of the type disclosed in the aforesaid U. S. Letters Patent No. 2,282,052. An upper housing 3 on such base 2 carries upwardly extending indicator casings 4 and 5 and a fixture including two work-piece supporting elements 6 and 1' adapted to have a work-piece such as connecting rod N temporarily mounted thereon.

Closely adjacent housing 3 on main base I is an upper housing 8 enclosing operating and control mechanism for probe 9 and face milling cutter Ii]. Such milling cutter is driven by electric motor I I through drive means enclosed Within guard I2, such housing 8 and motor ll being carried together on a slide 13 mounted on ways 14 (see Figs. 3 and 8) for reciprocation toward and away from such scale housing 3.

Also carried by base I is a slide [5 mounted on ways l6 parallel to ways 14 and carrying hollow milling cutter housing I1. Such hollow milling cutter is driven by electric motor I8 likewise mounted on slide l5 through drive means enclosed in guard I9. Hollow milling cutter 20 thus projects in a direction normal to the axis of face milling cutter ID.

A work holding fixture 2| is mounted on base I to support the work W in position to be engaged by such two milling cutters. Adjacent thereto is the gauging mechanism 22 adapted to cooperate with adjustable stop 23 mounted on slide l5 to control the depth of cut of the hollow milling cutter 20.

GENERAL OPERATION The scales are adjusted in the maner explained in Patent No. 2,282,052 by employment of a master connecting rod or other work-piece. Thereafter, when the operator places a work-piece upon elements 6 and '1 of the scales, the dial indicators 24 and 25 will show the amounts by which the crankshaft end and the wrist pin end of the connecting rod are overweight. In accordance with prior art practice, it would then be necessary for the operator to note such readings and properly to adjust the milling machines or other machine tools to remove the proper amount of metal from such respective ends of the connecting rod when the latter is transferred thereto. In accordance with the present invention, however, the operator may ignore the dial readings of the scales since such machine tools will automatically be preset through operation of selsyn means (described below) controlled by such scales. The operator need merely manually transfer the work-piece from the scales to the work holding fixture 2| where the same is firmly clamped in place. As soon as the work-piece is clamped, the slide 15 will advance a controlled distance and hollow milling cutter 29 carried thereby will automatically remove the proper amount of metal from the wrist pin end of the connecting rod. Simultaneously, probe 9 will advance from housing 8 and engage the crankshaft end of the connecting rod, face milling cutter [0 moving outwardly therewith. Upon completion of such probing operation, slide I3 carrying such housing and face milling cutter is traversed from left to right as viewed in Fig. l to cause such cutter to remove the proper amount of metal from the crankshaft end of the connecting rod, a small boss or protuberance having preferably been left on such end of the connecting rod for this purpose. It is obvious, of course, that the respective end portions of the connecting rod should not be underweight prior to the machining operations.

The slides automatically return to starting position (to the left as viewed in Fig. 1) and the work-piece is thereupon automatically unclamped for removal by the operator. As soon as probe 9 has moved into advanced position and slide l5 has returned, the operator may place another work-piece on the scales for weighing and presetting of the machine tool control means so that he may be ready to replace the finished work-piece removed from the clamping fixture with a minimum of delay.

Before explaining in detail the operation of our new machine, the various component units of the embodiment illustrated in the annexed drawing will first be described.

FACE MILLING UNIT Now referring more particularly to Figs. 7-12 of the drawing, such unit comprises a spindle 26 journalled in a quill 2'! mounted for limited reciprocation in housing 8. A key 28 engaging in keyway 29 holds such quill against rotation. Milling cutter I8 is carried by one end of such spindle and a gear 39 is keyed to the other end thereof. Meshed with such gear is a drive gear 3| of sufficient axial dimension to permit such reciprocation of quill 2! (see Fig. 7) and adapted to be driven through pulley 32, belts 33, and pulley 34 by motor II, the belts and pulleys being enclosed within guard 12. A lubricant pump 35 may conveniently be mounted for operation by the same drive means.

Surrounding quill 27 is a split sleeve 36 clamped thereon by bolts 31 (Fig. 11) and keyed thereto by key 38. A laterally extending bracket 39 (Fig. 7) is cored at 49 to receive probe rod 4| for reciprocation therein parallel to quill 21. A key 42 fitting in keyway 43 holds such rod against rotation and a nut 44 serves to limit reciprocation of the rod. A heavy compression spring 45 encircling rod 4! is interposed between bracket 39 and collar 46 having a sliding fit on such rod, such spring tending to urge probe 9 outwardly to the extent permitted by nut 44.

An outer extension 41 of rod 4!, of somewhat greater diameter, passes through bushing 48 in bracket 49 mounted on the inner wall of housing 8 and then through an outer bearing 59. Bushing 48 is mounted for reciprocation relative both to extension 4'! of the probe rod and to bracket 49. A compression spring 5|, weaker than spring 45, engages collar 52 of such bushing 48 normally to hold the latter against bracket 49 as shown in Fig. 9, for example.

Probe 9 is threaded into socket 53 in the end of the probe rod for delicate axial adjustment, being secured in place by longitudinally slotted collet portion 54 and nut 55 in conventional manner.

A downward extension 56 of bracket 39 is secured to the end of piston rod 51 of a fluid pressure piston-cylinder assembly comprising piston 58 in cylinder 59 whereby such bracket, and therefore quill 27, may be reciprocated to the extent permitted in one direction by coaeting steps 38 and 5| and in the other direction by control means now to be described (Fig.8).

A selsyn controlled drive motor 62 (Fig. l) operated in response to actuation of the scales supporting the crankshaft end of connecting rod W turns shaft 63 and thereby shafts 64 and 65 (Fig. 8) through bevel gearing 66, 61 and 68, 69. Gear 66 is slidingly keyed on shaft 63 to permit traversing of slide I3 on ways 14, housing 8 moving therewith. Shaft 65 has a pinion l0 keyed to its inner end (Figs. 7 and 8) engaging rack teeth on one side of a wedge member ll supported for reciprocation by rollers such as 12, 13, 14, the inclined face of such wedge being presented towards probe rod carrying bracket 39. The adjustment of this wedge determines the amount of stock to be removed from the crankshaft end of the connecting rod.

A plunger 15 (Fig. 8) is mounted in and extends through bracket 39 parallel to and above probe rod 4|, one end of such plunger being provided with an enlarged head 16 beveled to correspond to the slope of wedge II and juxtaposed thereto. A compression spring 11 interposed between said head and a shoulder of the bore in which plunger 15 is mounted tends to urge the plunger toward wedge H. The other end of the plunger protruding from bracket 39 carries a stand 18 on which is mounted limit switch I9 and limit switch operating lever 80. The lower end of such lever normally projects slightly beyond this end of plunger 15 which is also beveled to correspond with a locating wedge means described below.

Bushing 48 which is mounted for reciprocation against the force of compression spring 5| is provided with rack teeth 8| meshed with pinion 82 on vertically extending pinion shaft 83 journalled in bracket 49 (Figs. '7, 9 and 10). A gear segment 84 is keyed to the upper end of shaft 83 in engagement with rack teeth on the side of a locating wedge 85 mounted for reciprocation in bracket 49. The sloping face of such wedge is presented toward the correspondingly beveled end of plunger 15.

While stops '60, 6| serve to limit extreme return movement of bracket 39 and quill 2!, the beveled end portion provided on head ll; of plunger will in normal operation first engage wedge H pushing such plunger to the left, as viewed in Fig. 8, against the force of spring 11. Before the piston-cylinder assembly 59, 59 now operates to advance bracket 39 and the associated parts carried thereby, control means (described later in connection with the detailed operation of the machine) actuates fluid pressure piston-cylinder assembly 86, 81 to shift wedge 88 to force beveled plunger 89 downwardly into locking engagement with a correspondingly beveled relieved area on the side of plunger '15 (see Figs. 8 and 11). Plunger I5 is accordingly prevented from shifting to the right, as viewed in Fig. 8, when bracket 39 is reciprocated to the left away from stock removal control wedge ll. Such fluid pressure piston-cylinder assembly 86, 8" and associated parts are all mounted on and travel with bracket 33 and quill 27.

When a connectingrod is placed on the scales, the slightly overweight crankshaft end of the same will cause shaft 33 to be rotated to shift stock removal control wedge ll accordingly. After the operation of the scale and the selsyn control means have caused the stock removal wedge H to be shifted, contacts controlled by the weighing unit will be closed causing piston 58 to be shifted to the right (Fig. 8) until stops '80 and BI engage. Plunger i5 is thereby forced to the left relative to bracket 39 to an extent depending on the setting of wedge H, and plunger 89 is brought down to hold plunger 15 in this position (spring Tl urging plunger 15 to the right).

After the connecting rod has been transferred to the clamping fixture 2 I the operator will press the start button to cause piston 58, and therefore bracket 39, to be shifted to the left, advancing both probe 9 and milling cutter I0. When collar 45 on probe rod 4| engages bushing 48, just before probe 9 contacts the end of the connecting rod, such bushing will be shifted to the left since spring 45 is stronger than spring 5I. Such shifting of bushing 48 (for a short distance only, since probe 9 soon contacts the work) rocks gear segment 84 to reciprocate locating wedge 85, such reciprocation ceasing the moment probe 9 contacts the work. Probe rod 4| is now likewise incapable of further advance and continued travel of bracket 39 and milling cutter quill 21 is only permitted by compression of spring 45 until the forward end of plunger 15 engages locating wedge 85. This rocks lever 80 to actuate limit switch I9 which controls operation of fluid pressure piston-cylinder assembly 90, 9I (Fig. 12) carried by a quill clamping member 92 bolted to the inside of housing 8. A wedge 93 is reciprocated by such piston and bears against roller 94 mounted on rod 95 extending downwardly through upper clamping member 92 and lower clamping member 96 pivotally connected thereto at 97. A compression spring 98 surrounding rod 95 and interposed between such clamping members normally urges the latter to unclamped position, and nuts 99 on the end of rod 95 engage the underside of member 96. Such operation of piston-cylinder assembly 90, 9I accordingly serves to clamp the milling cutter quill firmly in housing 8 and the latter may now be traversed on its ways to make the cut.

HOLLOW IVIILLING UNIT Now referring more particularly to Figs. 1, 2 and 21, the hollow milling cutter 20 is driven in conventional manner by electric motor I8 through pulley I00, belting IOI, pulley I02, gears I03 and I04, and spindle I05 journalled in housing IT. The slide I5 supporting such housing is adapted to be reciprocated on ways I6 to advance cutter 20 into the wrist pin end of the connecting rod clamped in fixture 2 I, such cutter being positioned to engage an annular boss concentric with the wrist pin opening.

As best shown in Figs. 4, 5 and 6, the gauging stop 23 is mounted in slide I5 for very limited reciprocation relative thereto. Such stop comprises a screw threaded into block I05 and secured in adjusted position therein by means of set screw I01. Block I05 is mounted for limited reciprocation in a recess I08 in the upper edge of slide I 5, being secured therein by means of studs I09 and I I threaded into slide I and having enlarged heads limiting outward movement of block I06 and stop 23. Four uniformly arranged compression springs III, H2, H3 and II4 urge block I05 outwardly against the heads of studs I09 and I ID. A micro-switch I I5 is mounted on the upper surface of slide I5 directly behind block I06 for engagement and actuation by screw II6 carried in upstanding bracket In on the upper surface of block I06. Screw H6 will be adjusted and locked in bracket I I! in position to engage microswitch II5 without actuating the latter when block I06 is held against the heads of studs I09 and H0 by the aforesaid compression springs. Thus, when stop 23 engages an immovable object, it will cause block I05 to be moved inwardly an extremely slight distance just sufiicient to actuate micro-switch I I5.

The gauging mechanism 22 (Figs. 1, 2, and 13-17 inclusive) comprises a stand H8 in which plunger H9 is mounted for reciprocation axially of stop 23 and another stand I20 housing the control mechanism adapted to determine the position of such plunger. A stock removal control wedge I2I is supported between rollers I22, I23, I24 and I25 for reciprocation transversely of the inner end of plunger I I 9, the inclined face of such wedge being presented toward the end of the plunger which is likewise beveled to correspond thereto. As in the case of the rollers which support stock removal control wedge 'II of the face milling unit described above, such rollers engage in shallow grooves in the corresponding sides of the wedge member. Referring now particularly to Figs. 15 and 16 of the drawing, it will be noted that such rollers I22I25 are mounted on slightly eccentric bearings on spindles within threaded bushings such as I20 and I21 provided with enlarged knurled ends I28 and I29 whereby the corresponding rollers may be adjusted in and out as desired. The spindles are locked with the eccentric bearings in desired position by means of nuts I30 and I3I threaded on the ends of such spindles.

A selsyn controlled drive motor I32 exactly similar to motor 02 (Figs. 1 and 22) is mounted in base I of the machine beneath the gauging mechanism 22 to drive pinion I33 through shaft I34, coupling I35, and shaft I36 (Fig. 15). Such pinion engages corresponding rack teeth on wedge member I2I to shift the latter back and forth in accordance with the operation of electric motor I82. A compression spring I31 within stand II8 bears against finger I38 extending downwardly from plunger I I9 to urge the latter toward stop 23. Such spring I3! is, however, considerably weaker than the sum total effect of springs IIII I'4 which urge stop 23 outwardly.

When the connecting rod is placed upon the scales, the overweight wrist pin end of the latter actuates mechanism operating through selsyn means (more particularly described in connection with the explanation of the detailed operation of the machine set forth below) to drive motor I32 to shift wedge I2I to determine the amount of metal to be removed by the hollow milling cutter. The operator transfers the connecting rod to the work clamping fixture 2 I, and after the connecting rod has been firmly clamped therein the operator presses the start button to cause the hollow milling cutter to be fed forward. Piston I39 is reciprocated in cylinder I40 to advance slide I5 carrying the hollow milling unit and the stop 23 (Fig. 21). When stop 23 engages the outer end of plunger II9, such plunger is pushed in thereby against the action of relatively weak compression spring I31 until the inner end of such plunger engages wedge I2I. The plunger now being rigid against further reciprocation, stop 23 is moved inwardly slightly against the action of springs III-I I4 to actuate micro-switch II5 controlling the supply of fluid pressure to cylinder I40 and reversing the action of the latter to return slide I5 and the hollow milling cutter carried thereby.

WORK HOLDING FIXTURE Referring now more particularly to Figs. 18 and 19 of the drawing, the work holding fixture 2I which is adapted to position and clamp the connecting rod during the milling operations comprises a stand I4I provided with two spaced work positionin plugs I42 and I43 adapted to fit in the crankshaft hole and the wrist pin hole re- 

